To identify quantitative chromosomal variations or markers corresponding to the neoplastic conversion of cell lines, with the ultimate hope of being able to characterize cells converted by viruses on the basis of these markers. For this purpose we want to: 1. Develop further exact "global" chromosome measurements, such as for lengths and area and test these on cells from Chinese hamster primary cultures, with a computer-based measuring system, PIQUANT. 2. Develop a computer-based measuring system for banding. These measurements will constitute a quantitative "fine structure". 3. Correlate global and fine structure chromosome measurements on cell lines transformed by viruses.